1. Field of the Invention
The present invention relates to an improved method and apparatus for use in the propagation of plants under aeroponic conditions, and more specifically to a method and apparatus for providing an intermittent spray of an aqueous plant growth composition to a chamber as a hydro-atomized mist for inducing and promoting the growth of roots on plant cuttings and the like suspended within the chamber.
2. Description of the Prior Art
The propagation of plants, such as cuttings, in order to promote the development of root, stem and leaf structures, in a closed chamber while subjecting the plant to an aqueous mist containing such additives as nutrients, fertilizers, and other growth promoting compositions, is an old and well-known procedure. See for example U.S. Pat. No. 2,431,890 issued Dec. 2, 1947, to M. A. Raines for "Method and Receptacle for Propagating Plants." More recently, a method and apparatus for the aeroponic propagation of plants is disclosed in U.S. Pat. No. 4,332,105 issued June 1, 1982, to I. Nir for "Apparatus and Method for Plant Growth in Aeroponic Conditions." The patent to Nir describes a method and apparatus in which plants are supported by a support member above the root portions thereof and the root portions are subjected to a nutrient mist directed thereto, with control and timing means for controlling the time and sequence of application of the mist. Nir utilizes a high pressure pump or pneumatic pressure for pumping a nutrient containing aqueous fluid to the various mist nozzles. Alternatively, Nir provides for the spraying of tap water from a water tap. However, such tap water spray does not include nutrients, hormones or the like.